Dissecting retractor for harvesting vessels

ABSTRACT

A surgical dissecting retractor for harvesting vascular conduits or vessels such as saphenous veins and the like is disclosed which dissects tissue and top and/or side branches from the vessel as it is advanced along a desired segment of the vessel via an entry incision in a patient&#39;s skin. The dissecting retractor is inserted while in a closed or “low profile” position to minimize trauma to the vessel and patient. Once installed above the vessel, the retractor is opened and locked to present a relatively “high profile”, thereby creating and maintaining an enlarged working space or tunnel in the region between the skin and the vessel being harvested. Completion of the vessel harvesting procedure proceeds with suitable surgical instruments for dissecting, ligating, cauterizing and/or clipping, with or without visualizing devices which comprise further adjunct features of the retractors in accordance with the invention. Upon completion of the harvesting procedure, the dissecting retractor is unlocked to allow it to collapse to the closed position for removal from the harvesting site. A single surgeon can perform the harvesting procedure utilizing fewer instruments and with minimal trauma or damage to the vessel.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of application Ser. No. 09/032,744filed on Feb. 27, 1998, now issued as U.S. Pat. No. 6,059,802. Thepriority of the prior application is expressly claimed, and thedisclosure of this prior application is hereby incorporated by referencein its entirety.

FIELD OF THE INVENTION

The present invention relates to methods and instruments for harvestingvascular conduits or vessel sections, such as the saphenous veins,radial arteries and the like from a patient. More particularly, thepresent invention relates to methods and instruments for creating andmaintaining a working space or tunnel over a vascular conduit or vesselin which other surgical instruments can be manipulated to complete theharvest of the vascular conduit or vessel section while minimizingtrauma to the vascular conduit or vessel section and the patient.

BACKGROUND OF THE INVENTION

For various surgical procedures, and most commonly for coronary arterybypass grafting (CABG), it is common to remove or “harvest” a vascularconduit or vessel section, such as an artery or vein, from its naturallocation in a patient's body and to use it elsewhere in the body. InCABG surgery, the vascular conduit is used to establish a bypass betweenan arterial blood source and the coronary artery being bypassed. Oftenan artery proximate the heart, such as one of the internal mammaryarteries, can be used as the bypass conduit. Alternatively, one or moreof the saphenous veins in the legs, or a radial artery in an arm, areused as the vascular conduit, and are sometimes preferred by somesurgeons in emergency situations, and where multiple bypass vessels areneeded. For patient's requiring multiple bypasses, a surgeon may use thesaphenous vein in addition to various arteries to revascularize apatient's heart.

The conventional surgical procedure used to harvest the saphenous veinand the like for use in the CABG surgery, is generally very traumatic toa patient. The procedure involves making a continuous incision in theleg for the full length of the desired vein section in order to provideadequate exposure for visualizing the vein and for introducing surgicalinstruments to sever, cauterize and ligate the tissue and side branchesof the vein. The incision must then be closed by suturing or staplingalong its length. Many patients suffer significant complications such asskin loss, infections and impaired healing, saphenous nerve damage,hematomas and may experience lower extremity discomfort for months. Theprocedure also leaves disfiguring scars, increases patient recovery timeand hospital stay and thus adds to the cost of the CABG procedure.

In an attempt to overcome these problems, less-invasive techniques forharvesting vessels have been developed, employing one or two smallincisions, generally one at each end of the section of vessel to beremoved. Blunt mechanical force is applied by introduction of severalsurgical instruments of successively larger diameters to first create aworking space in the tissue surrounding the vein while separating thevein from the surrounding tissue. Then further multiple instruments areintroduced into the generally limited working space to dissect, clipand/or cauterize side branches of the vessel to allow harvesting of thedesired section of the vessel. An endoscope generally is required forsuch a procedure to enhance visualization of the vessel and thesurrounding tissue in the rather limited working space, particularly ata distance from the incision.

Even where these less invasive techniques reduce the overall length ofthe incision, the trauma to the vessel, the surrounding tissue and tothe patient can be severe. In particular, the harvesting procedureitself may actually be lengthened and the trauma to the vesselpotentially increased due to the number of surgical instruments that areneeded for the harvesting procedure, and due to the fact that theinstruments are reintroduced through the incision into the limitedregion between the patient's skin and vein. The trauma to the vessel aswell as to the patient is exacerbated by the condition that thepatient's skin and associated fat globules and tissue tend to collapseabout the saphenous vein. It follows that in each withdrawal andsubsequent insertion of a surgical instrument into the region above thevessel may cause added irritation, damage and trauma to the vessel. Anick in the vessel or damage to a side branch of the vessel causesundesirable problems since any damage to the harvested section of vesselmust be repaired before it can be used as a graft. The repairsthemselves are undesirable since they can lead to subsequent failure ofthe graft at the point of the damage and repair.

SUMMARY OF THE INVENTION

The goal of the present invention is to reduce the trauma and damage tothe vessel being harvested as well as to the patient by providing thecapability to more rapidly and less traumatically harvest the vessel. Tothis end, the invention is used to facilitate the creation of a workingspace around or above the vessel to be harvested. The working spacecreated by the installation of the invention can then be enlarged if sodesired. The enlarged working space can then be fixed and maintained bythe invention itself, thereby minimizing the trauma caused by subsequentmultiple insertions and withdrawals of additional surgical instruments.In addition, the invention enables a single surgeon to conduct theharvesting procedure.

Generally, the present invention includes an elongated slat assemblyhaving a longitudinal axis and a width dimension transverse to thelongitudinal axis, and means associated with the elongated slat assemblyfor varying the width dimension of the slat assembly. The elongated slatassembly provides a distal dissecting edge which preferably has apointed tip for facilitating dissection of tissue away from the vesselto be harvested.

The slat assembly preferably includes at least two slats which arelaterally translatable relative to each other. In one embodiment, thereis an upper and a lower slat having similar cross-sections across theirwidth dimensions. Preferably, the cross-section across the width of theslat assembly, and thus the individual slats, is arcuate. The means forvarying the width dimension comprises means for laterally translatingthe slats relative to each other. Such means for laterally translatingincludes, for example, a handle at the proximal end of each slat.

To further enable the lateral translation of the assembly, a series ofslots are formed in one of the slats and a corresponding series of pinsare secured to the other slat with each pin being slidably contained bya corresponding slot. The slots may be formed at a selected anglerelative to the longitudinal axis of the slat assembly or, alternately,slots are formed substantially transverse to the longitudinal axis. Inthe former design, the selected angle is preferably within the rangefrom about 35° to about 90°. In a preferred design, the dissectingretractor includes means for maintaining an enlarged width dimensionsuch that the width is greater than the minimum dimension and such thatthe width dimension can be fixed while a surgical procedure isconducted. Thus, when expanded, the retractor provides a stable, fixed,and maintained working space during the procedure. In the slot and pinembodiment, each slot includes a lock notch to enable a smalllongitudinal movement of the pins into respective lock notches tomaintain the width dimension of the working space.

Another aspect of the invention includes a stand adjustably secured torespective handles for selectively raising the position of the elongatedslat assembly to enlarge the working space above the vessel section tobe harvested. Each stand includes a stand slot formed along the lengththereof, a foot formed at a base of the stand, and bolt means disposedthrough the stand slot and threadably secured to the respective handle.In this way, each stand is vertically adjustable relative to therespective handle to maintain the selective raising of the position ofthe elongated slat assembly when the bolt means is tightened.

A method of using the present invention involves providing an elongateddissecting retractor for dissecting tissue and top and/or side branchesfrom a vessel, such as the saphenous vein, a radial artery, or the like,during insertion of the dissecting retractor via an entry incision. Onceinstalled, the invention maintains a working space in the region betweenthe skin and the vein to act as a guide while allowing less traumaticmanipulation of further surgical instruments, such as a ligatinginstrument, during the harvesting procedure. To this end, the dissectingretractor presents a low profile during its insertion, and subsequentremoval, along the vessel via the entry incision. Further, the retractoris adapted to be expanded after installation to present a high profileand thus an expanded working space or tunnel above a selected length ofvessel corresponding to the vessel section to be harvested. It followsthat the use of any additional surgical instrument to complete theharvesting procedure is accomplished with less trauma to the vesselsection even in the event that multiple insertions of surgicalinstruments is required.

In contrast to many of the vessel harvesting procedures practiced in thepast, the use of the dissecting retractor of this invention requires theuse of only a single instrument, the slat assembly, to separate thesubcutaneous tissue from the vessel along a length of the vessel. Aswill be appreciated from the accompanying description, the slat assemblyis inserted only once along the vessel, such as the saphenous vein. Whenrepositioned to reorient the individual slat assemblies, the amount ofretraction necessary to complete the harvesting procedure is essentiallycomplete.

Note also that the repositioning of the slats relative to one anotherhas the effect of increasing the surface area of the slat assembly whicheffectively amounts to the sum of the areas of the individual slats thatare exposed when the instrument is repositioned from the “closed to” apartially or completely “open” position. The retraction achieved by theslat assembly is mechanical and bidirectional in nature because itrelies on the rigid slat assemblies to move the tissue from the exertionof force along the length of the respective slats. The direction of theretraction is also dictated by the positioning of the slats in anorientation that is substantially parallel to the vessel to be harvestedas seen in FIG. 1. Thus, the present invention enables a biodirectionalmechanical retraction operation, subsequent to the positioning of theinstrument along a length of the vessel and which is substantiallyparallel to the vessel to be harvested.

More particularly, the dissecting retractor of the invention comprisesan elongated slat assembly or structure which includes a pair ofelongated slats or blades preferably formed of a rigid or semi-rigidplastic material such as a glass filled polymer, or any otherbiocompatible medical grade plastic as well as a stainless steel, etc.The elongated slats preferably have an arcuate cross-section with anupper arcuate slat concentrically disposed upon a lower arcuate slat toallow the slats to slide a selected distance circumferentially as wellas axially relative to each other. The distal end of either slat, butpreferably the upper slat, is formed to define a tip which may be fairlypointed or sharp or to define a blade-like edge to facilitate theseparation of tissue and side branches from a saphenous vein and thelike as the dissecting retractor is advanced under the skin through anentry incision.

In one embodiment, the upper slat includes a spaced series oftransversely, or preferably diagonally, arranged slots across the widthof the slat. The lower slat includes a correspondingly spaced series ofpins selectively fixed thereto with the heads of the pins extending fromthe lower slat in register with respective slots in the upper slat. Theheads of the pins thus slidably secure the upper slat to the lower slatwhen assembled together. A handle is formed at the proximal ends of eachof the upper and lower slats. When the handles, and thus the retractorare in a “closed” condition, the lower slat is nestled under and withinthe upper slat. Thus, the dissecting retractor presents a relatively lowprofile cross-section which facilitates advancing the distal tip of theretractor under the skin to thereby dissect the tissue and side branchesfrom the saphenous vein as the tip of the dissecting retractor isadvanced. When the dissecting retractor is in place above the length ofthe saphenous vein to be harvested, the handles are spread apart to“open” the retractor. In the open position, the lower slat iscircumferentially displaced from its nestled position beneath the upperslat, thereby expanding the cross section of the slats and specificallythe width and depth of the tunnel, or working space, created under theopened slats immediately above the length of vein. The retractor remainslocked in place during the harvesting procedure and guides unobstructedinsertions and withdrawals of a surgical instrument such as a ligatinginstrument, since the surrounding skin and tissue is held away from theworking space over the saphenous vein. It follows that the visualizationof the vein is much improved with or without use of an endoscope.However, the dissecting retractor may be modified in accordance with theinvention for use with endoscopic or fiberoptic lighting devices, ifdesired.

Therefore, several modifications and alternative embodiments arecontemplated in accordance with the invention as further disclosed inthe following description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating an embodiment of a dissectingretractor of the invention in a “high profile” opened position.

FIG. 2 is a top view of the embodiment of FIG. 1 in the opened position.

FIGS. 3, 4 and 5 are top, side and end views respectively of theinvention of FIGS. 1 and 2, in a “low profile” closed position.

FIG. 6 is a cross-sectional view taken along section line 6—6 of FIG. 3,with the retractor in the low profile closed position.

FIG. 7 is a cross-sectional view taken along section line 7—7 of FIG. 2,with the retractor in the high profile opened position.

FIG. 8 is a cross-sectional view of a fragment of a lower slatillustrating a pin configuration which is integrally pre-formed with theslat.

FIG. 9 is a cross-sectional view of a portion of the retractorillustrating a modified embodiment employing a slotted lumen in thelower slat, through which an endoscope or a fiberoptic light device maybe slidably disposed to facilitate visualizing the length of thesaphenous vein during the harvesting procedure.

FIG. 10 is a partial bottom view of the embodiment of FIG. 9 furtherillustrating the slotted lumen within which the endoscope or lightdevice is translatable.

FIGS. 11 and 12 are end and side views respectively of another modifiedembodiment of the invention.

FIGS. 13 and 14 are top views of a further embodiment of the inventionin closed and opened positions respectively.

FIG. 15 is a fragmentary, exploded, perspective view of anotherembodiment of the invention wherein the pins are located on the upperslat and the slots are formed in the lower slat.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a preferred embodiment of the dissecting retractor 20of the present invention, in a relatively “high profile” opened positionover a vessel 18 such as a saphenous vein, a radial artery, etc. Theinvention comprises an elongated slat assembly or structure whichincludes a lower blade or slat 22 nestled beneath an upper blade or slat24, wherein the slats are preferably arcuate in the direction of theirwidths and form an arcuate cross section. The arc of each slat hasessentially the same radius, and the width and thickness of the lowerslat 22 generally is less than the width and thickness of the upper slat24, so that the lower slat 22 fits snugly within the arcuatecircumference of the upper slat 24 when the retractor is in a “lowprofile” closed position. See for example FIG. 6. The distal end 27 ofthe upper slat 24 preferably extends beyond a distal end 28 of the lowerslat 22. Preferably, distal end 27 of upper slat 24 defines a downwardcurving configuration and terminates at a pointed and sharpened tip 26.

To facilitate the process of installing the dissecting retractor 20, theretractor may be oriented into the low profile or closed position, asillustrated in FIGS. 3-6, which presents a minimal cross section andalso presents tip 26 as the leading edge of the dissecting retractor toperform the function of dissecting tissue and top and/or side branchesfrom a vessel 18 as the surgeon advances the dissecting retractor alongthe vessel via an entry incision (not shown).

Referring to FIGS. 1 and 2, proximal ends 30, 32 of the upper and lowerslats 24, 22, respectively, have respective handles 34, 36 integrallyformed thereto, which handles extend generally perpendicular to thelengths of the respective slats. When the slats are in the closedposition, the handles 34, 36 extend upward in side-by-side configurationso that they can be grasped by one hand for insertion of the dissectingretractor. The handles 34, 36 are configured, at the points ofattachment to upper and lower slats 24, 22, to allow the handles to bepositioned in close proximity when the dissecting retractor 20 is in theclosed position. Thus, the width of either handle is less than thelength of the arc defined by the upper or lower slats 24, 22respectively. Preferably, a cut-out portion of the upper slat 24 isprovided to allow conforming engagement of the handle 36 affixed tolower slat 22 with the handle 34 of upper slat 24 to allow the upwardlyextending handles to be positioned as close to one another as possible.This configuration is best illustrated in the right side of FIG. 1.Essentially, a half portion of a short length of the proximal end 30 ofthe upper slat 24 is removed to provide space for the upwardly extendinghandle 36 of the lower slat 22 when the retractor is in the closedposition. When it is desired to move the slats 22, 24 to the openposition, the handles 36, 34 are spread apart a selected distance asdepicted in FIGS. 1, 2 and 7 and further described below.

To vary the width dimension of the slide assembly, the upper slat, 24 isprovided with a series of spaced, identical slots 38 which, in thisembodiment, extend diagonally at a selected angle across a major portionof the slat's width. See, for example FIGS. 1, 2 and 3. The slots 38terminate at similar ends in a lock notch 40, whose relatively shortlength extends generally parallel with the length of the slat 24. Thelock notches 40 are used to lock the retractor 20 in the high profileopened position, as further described below. A corresponding series ofpins 42 having heads of a selected type and diameter and are molded,screwed into, or otherwise securely fastened to the lower slat 22. Thepins 42 are preferably spaced apart the same distances as are thecorresponding slots 38 so that each slot has an associated pin.Installation of the pins 42 through their respective slots 38 and intothe slat 22, provides assembly of the upper slat 24 to the lower slat 22while allowing translation therebetween in the direction of the diagonalslots 38 and of the lock notches 40. The heads on the pins 42 may be ofround head or flat head configuration, and preferably are recessed orcountersunk within the slots 38 and lock notch 40 so that they do notsnag tissue when the retractor is being installed and used. See forexample FIGS. 6, 7 and 8. The slot-and-pin-type assembly is merely oneexample of a mechanical configuration that varies the width of the slideassembly. Others include a lead screw or other mechanical expedient.

When it is desired to remove the dissecting retractor from the harvestsite, such as upon completion of the harvesting procedure, in thisembodiment, the pins 42 are unlocked from the lock notches 40 by pushingthe lower slat 22 distally relative to the upper slat 24, and thehandles 34, 36 are closed together to return the retractor to the closedlow profile position. The retractor then is withdrawn from theharvesting site via the entry incision.

Pins 42 may be formed of a metal such as, for example, stainless steel,however it is to be understood that the pins 42 may be pre-formed of aplastic material similar to that of which the slats 22, 24 and handles34, 36 are formed. That is, referring particularly to FIG. 8, lower slat22 may be formed in a molding process including the handle 36, withpre-formed plastic pins 42′ integrally formed with the slat 22. Theheads of the pre-formed pins 42′ include a partially beveled top surface44 and a countersunk lower surface 46 to allow the pins 42′ to besnapped into respective similarly beveled slots 38. See FIGS. 6, 7 andparticularly FIG. 8. As may be seen, the heads of the pins 42 and/or 42′thus are countersunk to lie flush with the upper surface of the upperslat 24. Accordingly it is to be understood that various types ofmaterials and various different configurations of slats, handles and/orpins may be employed to form the components of the dissecting retractorof the present invention.

FIGS. 9 and 10 illustrate a modified embodiment of the present inventionwherein the lower slat 22 is modified to include a partially exposedlumen 50 which generally extends the length of lower slat 22. The lumen50 is formed within the thickness of lower slat 22 and is exposed alongan arcuate lower portion of its length to the minimal working spacecreated beneath the lower slat 22 when the retractor is closed, and tothe expanded working space formed under the lower and upper slats 22, 24when the retractor is opened. An endoscope or a fiberoptic light device,herein indicated by numeral 52, may be inserted in the lumen 50 and maybe translated along the lumen to any position along the retractor whichis desired to visualize a corresponding location along the saphenousvein, radial artery or the like, depicted by numeral 18 in FIG. 9. FIG.10 illustrates the use of an endoscope 52 which may be translated alongthe lumen 50 to selectively position a lens 54 of endoscope 52 in adesired position relative to the vessel. A fiberoptic light device maybe similarly used and positioned.

Referring to FIGS. 11 and 12, an alternative modification of the presentinvention provides means for further enlarging the working space createdby the dissecting retractor after installation over a vessel via anentry incision. To this end, each of the handles 34, 36 is provided withan adjustable stand 56, 58, respectively, which terminate at the lowerends thereof in a respective foot 60, 62. The bottom of each foot ispreferably provided with a high traction material or surface 64 toprevent any slippage of the retractor relative to the harvesting site.The stands 56, 58 are provided with respective stand slots 66, 68, andeach include respective bolts 70 threaded at one end and provided with aknurled knob 74, 76 at the other end. A threaded bore (78 in FIG. 12) isprovided in each handle 34, 36 to threadably receive the threaded ends(80 in FIG. 12) of respective bolts 70. As may be seen, once thedissecting retractor is installed in place, loosening the bolts 70 andlowering the stands 56, 58 relative to the handles 34, 36 tends to raisethe proximal ends 30, 32 of the retractor. This in turn, furtherenlarges the working space available above the vessel being harvested.Tightening the knobs/bolts secures the stands 56, 58 and the raiseddissecting retractor in place. It follows that a surgeon working alonecan proceed with completion of the vein harvesting procedure withsuitable surgical scissors, ligating instrument, cauterizing instrumentand/or surgical clips as required, and with or without visualizinginstruments such as the endoscope or fiberoptic light device 52 ofprevious mention. That is, use of the adjustable stands 56, 58 can allowa surgeon to perform the harvesting under direct visualization, withoutneed for an endoscope or light device.

FIGS. 13 and 14 illustrate a further modification of the previousembodiments of the invention, namely, the re-orientation of the diagonalslots 38 of the previous figures to illustrate generally transverseslots 84 relative to the length of an upper slat 86, which otherwise issimilar to the slat 24 of previous description. The slots 84 terminateat similar ends in respective lock notches 88 which extend a shortdistance in a generally longitudinal direction of the upper slat. FIG.13 illustrates the dissecting retractor in a closed low profile positionused when the retractor is advanced through an entry incision andprovides dissection of tissue and top and/or side branches by means ofthe sharpened tip 26.

FIG. 14 illustrates the retractor after it has been installed inposition and opened to present a high profile to create an enlargedworking space over the vein or artery to be harvested. The lower slat 22is locked in the open position relative to the upper slat 86 by shiftingthe lower slat proximally to engage the pins 42 (or 42′) in the locknotches 88. This maintains an enlarged width dimension and prevents theretractor from collapsing and closing due to the forces applied by thesurrounding tissue and skin, until desired by the surgeon.

FIG. 15 illustrates an alternative embodiment of the invention whereinthe positioning of the pins and associated slots are reversed. That is,a lower slat 92 corresponds to the lower slat 22 and an upper slat 94corresponds to the upper slat 24, of previous description, except that aseries of slots 96, similar to the previous slots 38 or 84, are formedin the lower slat 92. Likewise, a corresponding series of pins 98,similar to the previous pins 42 or 42′, are secured to or formed withthe upper slat 94. In this configuration, the upper surface of the upperslat 94 is smooth along its entire length with no obstructions to thetissue and branches during the procedures of installation and expandingof the dissecting retractor in accordance with the invention.

Accordingly, although the present invention has been described hereinrelative to specific embodiments and modifications, various additionalfeatures and advantages will be apparent from the description anddrawings, and thus the scope of the invention is defined by thefollowing claims and their equivalents.

What is claimed is:
 1. An apparatus for harvesting a section of vesselfrom a patient, comprising: an elongated slat assembly having alongitudinal axis and a width dimension transverse to said longitudinalaxis, said elongated slat assembly including at least two slatslaterally translatable relative to each other and having similar arcuatecross-sections at said width dimensions; and a structure associated withsaid elongated slat assembly for laterally translating two slats to varysaid width dimension of said elongated slat assembly.
 2. The apparatusof claim 1 wherein said elongated slat assembly comprises a distaldissecting edge.
 3. The apparatus of claim 2 wherein said distaldissecting edge comprises a pointed tip.
 4. The apparatus of claim 1wherein said elongated slat assembly includes an upper and a lower slatdisposed for lateral translation in overlapping relationship.
 5. Theapparatus of claim 1 wherein said structure for varying said widthdimension includes slidable fasteners for laterally translating saidslats relative to each other.
 6. The apparatus of claim 1 wherein saidstructure for laterally translating comprises a handle attached at aproximal end of each said slat.
 7. The apparatus of claim 5 wherein saidslidable fasteners comprises: a series of slots formed in one of saidslats at a selected angle relative to said longitudinal axis; and acorresponding series of pins secured to the other of said slats witheach pin slidably contained by a corresponding slot for enabling thelateral translation between the slats at the selected angle.
 8. Theapparatus of claim 7 wherein said series of slots are formed in saidupper slat and said series of pins are secured to said lower slat. 9.The apparatus of claim 7 wherein said series of slots are formed in saidlower slat and said series of pins are secured to said upper slat. 10.The apparatus of claim 7 wherein each said slot includes a lock notchskewed from the selected angle to substantial alignment with saidlongitudinal axis to enable longitudinal movement of said pins intorespective lock notches.
 11. The apparatus of claim 7 wherein saidseries of slots are formed substantially transverse to said longitudinalaxis.
 12. The apparatus of claim 7 wherein said selected angle is withinthe range from about 35° to about 90°.
 13. The apparatus of claim 1wherein each stand is comprised of: a stand slot formed along the lengththereof; a foot formed at a base of said stand; and bolt means disposedthrough said stand slot and threadably secured to said respectivehandle; each stand being vertically adjustable relative to therespective handle to maintain the selective raising of the position ofsaid elongated slat assembly when said bolt means is tightened.
 14. Anapparatus for harvesting a vascular conduit for use in coronary arterybypass grafting, comprising: an elongated structure having distal andproximal ends and including a first elongated arcuate slat, and a secondelongated arcuate slat nestled within said first slat to define anarcuate low profile cross section adapted to atraumatically dissecttissue and branches as said distal end of said structure is advancedalong the vascular conduit; and means for laterally expanding saidelongated structure to define a high profile structure which creates anenlarged working space above the vascular conduit.
 15. The apparatus ofclaim 14 wherein: said means for laterally expanding includes aplurality of slots formed at a selected angle in one of said slats, anda corresponding plurality of pins secured with said other slat forslidable containment in respective slots to enable said slats tolaterally expand at said selected angle.
 16. An apparatus for harvestinga section of vessel from a patient, comprising: an elongated slatassembly including at least two slats laterally translatable relative toeach other and having a longitudinal axis and a width dimensiontransverse to said longitudinal axis, said elongated slat assemblyincluding an upper and lower slat having similar cross-sections at saidwidth dimension; and means associated with said elongated slat assemblyfor laterally translating said slats relative to each other including ahandle at the proximal end of each of said slat for varying said widthdimension of said elongated assembly; and a stand adjustably secured toeach of said handles for selectively raising the position of saidelongated slat assembly to enlarge the working space above the vesselsection to be harvested.
 17. An apparatus for harvesting a vascularconduit for use in coronary artery bypass grafting, comprising: anelongated structure having distal and proximal ends and including afirst elongated arcuate slat, and a second elongated arcuate slatnestled within said first slat to define an arcuate low profile crosssection adapted to atraumatically dissect tissue and branches of thevascular conduit as said distal end of said structure is advanced alongthe vascular conduit; and means for laterally expanding said elongatedstructure including a plurality of slots formed at a selected angle inone of said slats, and a corresponding plurality of slots formed at aselected angle in one of said slats, and a corresponding plurality ofpins secured with said other slat for slidable containment in respectiveslots to enable said slats to laterally expand at said selected angle todefine a high profile structure which creates an enlarged working spaceabove the vascular conduit, said means further includes a handleintegral with said proximal end of a respective slat for applyinggenerally outwardly forces on said handles to cause one slat to sliderelative to said other slat in the direction corresponding to saidselected angle.
 18. The apparatus of claim 17 further including meansfor locking said pins in said respective slots when said slats areexpanded to maintain said high profile structure.